Radio-frequency excited gas lasers are common particularly for relatively low power lasers. Excitation is provided by a radio-frequency electric field produced in the laser active medium which produces population inversions within the gas. Usually the field is produced by electrodes excited by a radio-frequency power supply. The power supplied to the laser is sufficient to cause the initial breakdown of the gas and is usually maintained at that level throughout the operation of the laser.
It has become apparent that a radio-frequency excited gas laser operates at maximum efficiency when the input power is less than the power which produces striking and/or maximum output. It is thus more economical to operate such a laser at its maximum efficiency point, particularly as the laser may readily be made to produce a desired power output when so operating. However, existing power supply circuitry does not make it possible to operate at the maximum efficiency point.